Corey and Steve talk with MSU Neuroscientist A.J. Robison about why females may be more likely to suffer from depression than males. A.J. reviews past findings that low testosterone and having a smaller hippocampus may predict depression risk. He explains how a serendipitous observation opened up his current line of research and describes tools he uses to study neural circuits. Steve asks about the politics of studying sex differences and tells of a start up using CRISPR to attack heart disease. The three end with a discussion of the psychological effects of ketamine, testosterone and deep brain stimulation.